<template lang="">
  <div class="pie-container">
    <div ref="pieRef" :style="{ width, height }"></div>
    <div class="text-tip">
      <span>
        {{ percent }}
      </span>
      <span>
        {{ text }}
      </span>
    </div>
  </div>
</template>
<script>
import * as echarts from "echarts";

export default {
  data() {
    return {
      text: "学生活动时间",
      percent: 0
    };
  },
  props: {
    allocationTime: {
      type: Object,
      default: () => {}
    },
    id: {
      type: String,
      default: ""
    },
    width: {
      type: String,
      default: "400px"
    },
    height: {
      type: String,
      default: "400px"
    }
  },

  computed: {
    focusFormat() {
      return (value) => {
        return parseFloat(value) || 0;
      };
    }
  },

  methods: {
    init() {
      const { allocationTime } = this.$props;

      const optionsData = [
        {
          name: "学生活动时间",
          value: this.focusFormat(allocationTime.student_time_per),
          itemStyle: {
            color: "#2D9BFC"
          }
        },

        {
          name: "教师授课时间",
          value: this.focusFormat(allocationTime.teacher_time_per),
          itemStyle: {
            color: "#0A9942"
          }
        }
      ];
      const dom = this.$refs.pieRef;
      const pieChart = echarts.init(dom);
      const series = this.getPie3D(optionsData, 0.8, 240, 28, 26, 0.5);
      series.push({
        name: "pie2d",
        type: "pie",
        label: {
          show: false,
          position: "center",
          opacity: 1,
          fontSize: 13,
          lineHeight: 20,
          textStyle: {
            fontSize: 12
          }
        },

        emphasis: {
          label: {
            show: false,
            fontSize: 12,
            fontWeight: "bold"
          }
        },

        labelLine: {
          length: 10
        },
        startAngle: -90, //起始角度，支持范围[0, 360]。
        clockwise: false, //饼图的扇区是否是顺时针排布。上述这两项配置主要是为了对齐3d的样式
        radius: ["50%", "90%"],

        center: ["50%", "50%"],
        data: optionsData,
        itemStyle: {
          opacity: 0
        }
      });
      // 准备待返回的配置项，把准备好的 legendData、series 传入。
      const option = {
        backgroundColor: "transparent",
        legend: {
          itemHeight: 12,
          itemWidth: 12,
          orient: "vertical",
          itemGap: 10,

          tooltip: {
            show: true
          },
          data: ["学生活动时间", "教师授课时间"],
          right: "0",
          top: "5%",
          textStyle: {
            color: "#B8C6CB",
            fontSize: 14,
            padding: [0, 8] // 设置图例文本的左右边距
          }
        },
        animation: true,

        title: {
          x: "center",
          top: "20",
          textStyle: {
            color: "#fff",
            fontSize: 22
          }
        },
        labelLine: {
          show: true,
          lineStyle: {
            color: "#7BC0CB"
          }
        },
        label: {
          show: false,
          position: "inside",
          formatter: "{d}% \n {b}"
        },
        xAxis3D: {
          min: -1,
          max: 1
        },
        yAxis3D: {
          min: -1,
          max: 1
        },
        zAxis3D: {
          min: -1,
          max: 1
        },
        grid3D: {
          show: false,
          boxHeight: 0.5,
          //top: '30%',
          bottom: "50%",
          environment: "#173566",

          viewControl: {
            distance: 140,
            alpha: 50,
            beta: 80,
            roam: true, // 禁止鼠标缩放平移
            autoRotate: false, // 自动旋转
            zoomSensitivity: 0
          }
        },

        series: series
      };

      pieChart.on("mouseover", (e) => {
        if (e.seriesType != "pie") {
          return;
        }
        this.text = e.name;
        this.percent = e.percent;
      });
      pieChart.setOption(option);
    },
    getPie3D(pieData, internalDiameterRatio) {
      let series = [];
      let sumValue = 0;
      let startValue = 0;
      let endValue = 0;
      let legendData = [];
      let k = typeof internalDiameterRatio !== "undefined" ? (1 - internalDiameterRatio) / (1 + internalDiameterRatio) : 1 / 3;

      // 为每一个饼图数据，生成一个 series-surface 配置
      for (let i = 0; i < pieData.length; i++) {
        sumValue += pieData[i].value;

        let seriesItem = {
          name: typeof pieData[i].name === "undefined" ? `series${i}` : pieData[i].name,
          type: "surface",
          parametric: true,
          wireframe: {
            show: false
          },
          pieData: pieData[i],
          pieStatus: {
            selected: false,
            hovered: false,
            k: k
          }
        };

        if (typeof pieData[i].itemStyle != "undefined") {
          let itemStyle = {};

          typeof pieData[i].itemStyle.color != "undefined" ? (itemStyle.color = pieData[i].itemStyle.color) : null;
          typeof pieData[i].itemStyle.opacity != "undefined" ? (itemStyle.opacity = pieData[i].itemStyle.opacity) : null;

          seriesItem.itemStyle = itemStyle;
        }
        series.push(seriesItem);
      }

      // 使用上一次遍历时，计算出的数据和 sumValue，调用 getParametricEquation 函数，
      // 向每个 series-surface 传入不同的参数方程 series-surface.parametricEquation，也就是实现每一个扇形。
      for (let i = 0; i < series.length; i++) {
        endValue = startValue + series[i].pieData.value;
        series[i].pieData.startRatio = startValue / sumValue;
        series[i].pieData.endRatio = endValue / sumValue;
        series[i].parametricEquation = this.getParametricEquation(series[i].pieData.startRatio, series[i].pieData.endRatio, false, false, k, series[i].pieData.value);

        startValue = endValue;

        legendData.push(series[i].name);
      }

      // // 补充一个透明的圆环，用于支撑高亮功能的近似实现。
      series.push({
        name: "mouseoutSeries",
        type: "surface",
        parametric: true,
        wireframe: {
          show: false
        },
        itemStyle: {
          opacity: 0.1,
          color: "#071921"
        },
        parametricEquation: {
          u: {
            min: 0,
            max: Math.PI * 2,
            step: Math.PI / 20
          },
          v: {
            min: 0,
            max: Math.PI,
            step: Math.PI / 20
          },
          x: function (u, v) {
            return ((Math.sin(v) * Math.sin(u) + Math.sin(u)) / Math.PI) * 2;
          },
          y: function (u, v) {
            return ((Math.sin(v) * Math.cos(u) + Math.cos(u)) / Math.PI) * 2;
          },
          z: function (u, v) {
            return Math.cos(v) > 0 ? -0.5 : -5;
          }
        }
      });

      // // 补充一个透明的圆环，用于支撑高亮功能的近似实现。
      series.push({
        name: "mouseoutSeries",
        type: "surface",
        parametric: true,
        wireframe: {
          show: false
        },
        itemStyle: {
          opacity: 0.1,
          color: "#071921"
        },
        parametricEquation: {
          u: {
            min: 0,
            max: Math.PI * 2,
            step: Math.PI / 20
          },
          v: {
            min: 0,
            max: Math.PI,
            step: Math.PI / 20
          },
          x: function (u, v) {
            return ((Math.sin(v) * Math.sin(u) + Math.sin(u)) / Math.PI) * 2;
          },
          y: function (u, v) {
            return ((Math.sin(v) * Math.cos(u) + Math.cos(u)) / Math.PI) * 2;
          },
          z: function (u, v) {
            return Math.cos(v) > 0 ? -5 : -7;
          }
        }
      });
      series.push({
        name: "mouseoutSeries",
        type: "surface",
        parametric: true,
        wireframe: {
          show: false
        },
        itemStyle: {
          opacity: 0.1,
          color: "#071921"
        },

        parametricEquation: {
          u: {
            min: 0,
            max: Math.PI * 2,
            step: Math.PI / 20
          },
          v: {
            min: 0,
            max: Math.PI,
            step: Math.PI / 20
          },
          x: function (u, v) {
            return ((Math.sin(v) * Math.sin(u) + Math.sin(u)) / Math.PI) * 2.2;
          },
          y: function (u, v) {
            return ((Math.sin(v) * Math.cos(u) + Math.cos(u)) / Math.PI) * 2.2;
          },
          z: function (u, v) {
            return Math.cos(v) > 0 ? -7 : -7;
          }
        }
      });
      return series;
    },
    getParametricEquation(startRatio, endRatio, isSelected, isHovered, k, height) {
      // 计算
      let midRatio = (startRatio + endRatio) / 2;

      let startRadian = startRatio * Math.PI * 2;
      let endRadian = endRatio * Math.PI * 2;
      let midRadian = midRatio * Math.PI * 2;

      // 如果只有一个扇形，则不实现选中效果。
      if (startRatio === 0 && endRatio === 1) {
        isSelected = false;
      }

      // 通过扇形内径/外径的值，换算出辅助参数 k（默认值 1/3）
      k = typeof k !== "undefined" ? k : 1 / 3;

      // 计算选中效果分别在 x 轴、y 轴方向上的位移（未选中，则位移均为 0）
      let offsetX = isSelected ? Math.cos(midRadian) * 0.1 : 0;
      let offsetY = isSelected ? Math.sin(midRadian) * 0.1 : 0;

      // 计算高亮效果的放大比例（未高亮，则比例为 1）
      let hoverRate = isHovered ? 1.05 : 1;

      // 返回曲面参数方程
      return {
        u: {
          min: -Math.PI,
          max: Math.PI * 3,
          step: Math.PI / 32
        },

        v: {
          min: 0,
          max: Math.PI * 2,
          step: Math.PI / 20
        },

        x: function (u, v) {
          if (u < startRadian) {
            return offsetX + Math.cos(startRadian) * (1 + Math.cos(v) * k) * hoverRate;
          }
          if (u > endRadian) {
            return offsetX + Math.cos(endRadian) * (1 + Math.cos(v) * k) * hoverRate;
          }
          return offsetX + Math.cos(u) * (1 + Math.cos(v) * k) * hoverRate;
        },

        y: function (u, v) {
          if (u < startRadian) {
            return offsetY + Math.sin(startRadian) * (1 + Math.cos(v) * k) * hoverRate;
          }
          if (u > endRadian) {
            return offsetY + Math.sin(endRadian) * (1 + Math.cos(v) * k) * hoverRate;
          }
          return offsetY + Math.sin(u) * (1 + Math.cos(v) * k) * hoverRate;
        },

        z: function (u, v) {
          if (u < -Math.PI * 0.5) {
            return Math.sin(u);
          }
          if (u > Math.PI * 2.5) {
            return Math.sin(u);
          }
          return Math.sin(v) > 0 ? 1 * height : -1;
        }
      };
    }
  },
  mounted() {
    this.$nextTick(function () {
      this.init();
    });
  }
};
</script>
<style lang="scss">
.pie-container {
  position: relative;

  .text-tip {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    position: absolute;
    top: 50%;
    left: 49%;
    transform: translate(-50%, -50%);
    span {
      margin-top: 10px;
    }
  }
}
</style>
